1. Field of the Invention.
The present invention relates generally to bicycle wheels and bicycle wheel hubs. More specifically, the invention relates to tangentially laced, tensioned spoked wheels for human powered vehicles (HPV's) such as bicycles, where spokes are grouped in pairs where they are connected to a hub for improved torque transmission and reduced spoke stresses at spoke crossover points. The invention is also concerned with such wheels comprising a hub, a rim, at least one sprocket, a first, proximate set of spokes and a proximate hub flange, adjacent to the at least one sprocket, and a second, opposed set of spokes and an opposed hub flange opposite the at least one sprocket wherein said spokes are paired at the hub flanges or wherein said proximate spokes extend towards the rim adjacent to an outside surface or sprocket side of the proximate hub flange and the opposed spokes extend towards the rim adjacent to an inside surface or sprocket side of the opposed hub flange, or both. The invention is also concerned with such a tangentially laced, tensioned HPV wheel which includes a disk, in place of the at least one sprocket, as in a front wheel used on a bicycle equipped with a disk brake.
2. Description of the Prior Art
Bicycle wheels are certainly known as are multi-speed bicycles with rear wheel hubs including a multiplicity of sprockets. In a conventional rear bicycle wheel with one or more sprockets, as well as a front wheel equipped with a disk, the wheel is "dished" meaning that a plane perpendicular to the axis of rotation of the wheel and mid-way between the flanges of the hub will be spaced from a plane perpendicular to the axis of rotation of the wheel and coinciding with the center plane of the rim. Reference is made to U.S. Pat. No. 5,228,756 ("Krampera"), the disclosure of which is incorporated herein by reference. In column one of this patent, there is a discussion of wheel dish.
The axle of a rear bicycle wheel is mounted in "drop-outs" in a bicycle frame. The rear wheel hub and at least one sprocket are mounted on the axle. The hub includes a hub flange adjacent to the sprockets, herein referred to as the proximal hub flange and a hub flange opposite the proximal hub flange, hereinafter referred to as the opposite hub flange. In a conventional dished wheel, the spokes which are attached to the proximal hub flange are under more tension than the spokes which are attached to the opposite hub flange. This has lead some inventors to connect the spokes to the rim at points which do not coincide with the center plane of the rim, reducing or even eliminating dish. This approach is illustrated and discussed in the Krampera patent. In dished wheels, the proximate spokes are at a higher tension than the opposite spokes.
Rear wheels and front wheels with disk brakes are tangentially laced so that, between the hub flange and the rim, the spokes will cross at least one or two and usually three other spokes, depending on the number of spokes and the lacing geometry. In conventional wheels, there is contact between the spokes where they cross and this can lead to problems ranging from noise to spoke failure. This contact and several approaches to eliminating such contact are discussed in U.S. Pat. No. 4,300,804 ("Hasebe"), the disclosure of which is incorporated herein by reference. This patent discloses various ways to mount the spokes at each of the two hub flanges, at two different axial locations but on the same side of the hub flange, thereby eliminating or reducing spoke interference. The Hasebe patent also includes an informative discussion in column one concerning the orientation of the spoke heads at the hub flange. In what it calls alternate assembly, spokes adjacent to each other on a given flange are inserted into spoke bores in the hub flanges from opposite sides of the hub flange. In this conventional design, interference between spokes at cross-over points is reduced by comparison with the case where all of the spokes are inserted through spoke bores from the same side of the hub flange. The Hasebe patent discloses modified hub flanges which reduce spoke interference when all of the spokes in a particular hub flange are inserted through the spoke bores from the same side of the hub flange. The patent teaches that all of the spokes are inserted through spoke bores from the "axially inside side" (column 2, line 23). As a consequence, in the Hasebe wheel, spoke interference is reduced, but the dish of the wheel remains the same.
U.S. Pat. No. 1,388,021 ("Budd") discloses a wire spoked wheel in which the spokes are tangentially oriented and are unbent over their entire length. The spokes are paired at the hub and seated in "shouldered blocks" 12 so that each of the two spokes that make up a pair cross each other between the hub and the rim. In each pair, the spoke heads at the ends of the spokes which are connected to the hub are staggered, as shown clearly in FIG. 1, in the sense that, where they are connected to the hub, they are at different axial locations.
French Patent No. 479,141 ("Delobre") discloses a tangentially laced spoked wheel in which spokes are grouped in pairs where they are connected to the hub flange. Like the wheel disclosed in Budd, each of the two spokes in a pair crosses the other and the spoke heads, where they are connected to the hub, are axially offset from one another as shown in FIG. 2.
U.S. Pat. No. 478,394 ("Bretz") discloses a tangentially laced spoked wheel in which spoke heads are connected to the hub and, specifically, to spurs "a" which extend radially outwardly from and are evenly spaced around the hub flanges.
U.S. Pat. No. 5,626,401 ("Terry, Sr. Et al.") discloses a tangentially laced spoked wheel with straight pull spokes. Spokes are paired, at the hub flanges, and the spoke heads are retained in retention cavities 75. The spokes in each pair are axially offset from one another at the hub.
U.S. Pat. No. 4,090,737 ("Jensen") discloses a radially laced spoked wheel in which spokes are grouped in groups of three at the hub.
U.S. Pat. No. 605,208 ("Skarin") discloses a tangentially laced spoked wheel in which spokes are paired at the hub flanges. The spokes in a given pair cross each other and are axially offset from each other.